Cross-contamination is a major food safety risk during the harvesting and processing of fresh produce, leading to significant losses in global human well-being and the economy. The surface of food contact areas is a high-risk zone for cross-contamination. Therefore, developing an effective antimicrobial coating for food-contact surfaces is essential. This study developed a smart antimicrobial coating that self-regulated in response to environmental conditions, via grafting the stimuli-responsive polymer polyacrylic acid (PAA) and the phage-derived endolysin Lysin81 onto ZnO nanocolumns. During the initial stage of bacterial adhesion, the surface of the nanocolumns exhibited significant mechanical bactericidal activity, while the super hydrophilic PAA layer effectively inhibited bacterial adhesion. At a later stage, when numerous live and dead bacteria adhered to the surface of the nanocolumns, the PAA chains disintegrated, exposing the underlying layer of endolysin that lysed the compromised bacteria. In addition, as the environmental pH increases, the attached dead bacteria can be released once the PAA chains regain their hydrophilicity. This research aimed to apply the antibacterial coating to stainless steel surfaces used in food processing, potentially enhancing surface hygiene and preventing cross-contamination of fresh produce.
Tao Liu,Cuijuan Zhang,Jiashu Yuan,Yihan Zhen,Yongdan Li
The non-aqueous redox flow batteries (NARFBs) are promising for large-scale energy storage. However, the crossover contamination of active materials seriously imparts the performance. Here, two-dimensional (2D) vermiculite nanosheets modified Celgard porous membrane is prepared by the filtration method. The 2D vermiculite nanosheet layers stacked on the surface of Celgard membrane effectively reduce the crossover effect by sieving electrolytes and active materials through the nanoscale intercalation channels. Furthermore, the surface-governed transport behavior of the 2D vermiculite nanosheets is conducive to the exchange of supporting electrolyte. The resultant NARFB with the modified membrane exhibits higher Coulombic efficiency (95.3% vs. 87.6%) and larger discharge capacity (0.104 vs. 0.093 Ah L −1 ) without obvious impact on voltage efficiency (90.1% vs. 90.5%) at 2 mA cm −2 . This work provides an efficient strategy to alleviate the crossover effect in NARFBs.
Kun Yin,Xi Zeng,Weizhi Liu,Yakun Xue,Xingrui Li,Wei Wang,Yanling Song,Zhi Zhu,Chaoyong Yang
As the third-generation nucleic acid amplification technology, digital polymerase chain reaction (PCR) has been widely adopted in the analysis of nucleic acids. However, further application of this powerful technology is hindered due to the limitation of surfactants. Here, for the first time, we propose the use of colloidosomes self-assembled from fluorinated silica nanoparticle for digital PCR to address this limitation. A one-step fluorinated silica nanoparticle synthesis method is proposed, which is much more convenient and reproducible compared with the synthesis of conventional fluorine-based surfactants. Fluorinated silica nanoparticles facilitate the formation of colloidosomes with excellent stability capable of enduring the rapid temperature changes associated with the PCR and avoiding material exchange (cross-talk) between droplets for high-fidelity analysis. The colloidosome digital PCR method was developed using these colloidosomes as highly parallel reactors for single-copy nucleic acid amplification and rare mutant detection. The method is robust and accurate, and it offers possibilities for a great variety of applications, such as gene expression studies, single cell analysis, and circulating tumor DNA detection.
危险品化学品经营许可证（带存储）